The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
This invention relates to fins used by swimmers for propulsion. More particularly, this invention is to a method of improving existing swim fins to make them more efficient.
Conventional swim fins have been manufactured in the past and present in typical set sizes such as xe2x80x9csmallxe2x80x9d, xe2x80x9cmediumxe2x80x9d, xe2x80x9clargexe2x80x9d and the like. Consequently, the user has been very limited in being able to choose a combination of overall features of the swim fins themselves but instead, has been generally required to select fins based upon the closest fit according to the user""s foot size. In other words, the xe2x80x9cfootxe2x80x9d or xe2x80x9cfin sizexe2x80x9d fixed every dimension and dynamic characteristic of the fin having that size selection. As the xe2x80x9cfootxe2x80x9d size dimension from fin to fin increased from say medium to large, then generally every contour and dimension of the fin also increased from fixed medium size to fixed large size. Thus, a user would not necessarily be able to choose a fin that would both simultaneously fit with comfort and also provide the desired hydrodynamic efficiency, size and shape for different tasks, and/or aesthetics. In this context, hydrodynamic efficiency may also be taken to mean hydrodynamic suitability (inefficiency) or resistance because it may be desired for example for fins to have increased inefficiencies and/or resistances for the purposes of exercise or training.
Many different hydrodynamic contours are possible in conventional fins and these contours may differ either greatly or only slightly from one another. However, the contours for swim fins have been fixed for given fin sizes, and these contours include contours of overall exterior/outermost surface outlines (exterior wings, paddles or individual blades), contours of surface features (ridges, bumps, indentations, stiffeners), contours of interior (passages, tunnels, vents or ports), and contours of foot openings (foot pockets or full foot enclosures). All of these contours control or affect hydrodynamic efficiency of fins to one degree or another as a result of fluid flow over the fin contours, or as a result of the mechanical flexure/rigidity which is a direct consequence of the combined contours (geometry) and material properties of the fins.
Thus, in accordance with this inventive concept, a need has been recognized in the state of the art for a method of reconfiguring existing swim fins for individual users to provide fit, comfort, energy use (in terms of efficiency of hydrodynamic design), requirements for different missions or aesthetics.
An object of the invention is to provide a method to reconfigure existing swim fins to modify hydrodynamic performance.
Another object of the invention is to provide a method of shaping existing swim fins to accommodate the needs of a user.
Another object of the invention is to provide a method of modifying existing swim fins to provide the additional and different capabilities of a large number of different swim fins without requiring an inventory of a commensurate large number of different swim fins.
Another object of the invention is to provide a cost-effective method of reshaping contours of existing swim fins to newer and more hydrodynamicly efficient modern designs.
Another object of the invention is to provide a method of selectively reshaping, or customizing existing swim fins that can be implemented at the time of sale to modify the hydrodynamic characteristics of the fins according to a buyer""s needs.
These and other objects of the invention will become more readily apparent from the ensuing specification when taken in conjunction with the appended claims.
Accordingly, the present invention is to a method of reshaping existing diving fins according to a user""s needs. An existing swim fin having a blade portion made from a rubber-like material extending from a body portion is placed on a flat work surface. A template is laid on the blade portion, and the outline of the template is traced onto the blade portion to define shape lines on it. The rubber-like material is removed from within the shape lines on the blade portion of the swim fin. The shape lines and the removed rubber-like material can extend from a trailing edge of the blade portion toward the body portion. Other contours are similarly formed in the swim fin since the method of the invention can readily modify and/or customize the fin""s contours according to the user""s needs or desires concerning fit, comfort, energy use, mission requirements and/or aesthetics.